This invention relates generally to surgical knives and other surgical devices and particularly to knives used in ophthalmic surgery.
For many years, the predominant method of treating a diseased lens has been to remove the diseased lens and replace it with an intraocular lens (“IOL”). Two surgical procedures are preferred for removing the diseased lens: extracapsular cataract extraction and phacoemulsification. Extracapsular cataract extraction involves removing the lens in a relatively intact condition by use of a vectus or similar surgical instrument. Phacoemulsification involves contacting the lens with the vibrating cutting tip of an ultrasonically driven surgical handpiece to emulsify the lens, thereby allowing the emulsified lens to be aspirated from the eye. Although extracapsular cataract extraction has been the preferred surgical technique, phacoemulsification has become increasingly popular, in part because the cutting tip of the ultrasonic handpiece requires only a relatively small (approximately 3 to 3.5 millimeter) tunnel incision.
A typical posterior chamber IOL comprises an artificial lens (“optic”) and at least one support member (“haptic”) for positioning the IOL within the capsular bag. The optic may be formed from any of a number of different materials, including polymethylmethacrylate (PMMA), polycarbonate, silicon and soft acrylics, and it may be hard, relatively flexible or even fully deformable so that the IOL can be rolled or folded prior to insertion. The haptics generally are made from some resilient material, such as polypropylene, PMMA or soft acrylic. IOL's may be characterized as either “one-piece” or “multi-piece.” With one-piece IOL's, the haptic and the optic are formed integrally as a blank and the IOL is then milled or lathed to the desired shape and configuration. Multi-piece IOL's are formed either by attaching the haptic to a preformed optic or by molding the optic around the proximal end of the haptic.
Endophthalmitis has always been a concern during ophthalmic surgery, and ophthalmic surgical procedures generally include the application of an intra-operative and/or post-operative antimicrobial agent; however, endophthalmitis can still occulr in a small percentage of cases.
Therefore, a need continues to exist for a device to help reduce the risk of endophthalmitis following ophthalmic surgery.